In a classic example of generational changes, thousands of young people showed their age by responding to the news of Kanye West’s single collaboration with Paul McCartney, one of the legends in the Beatle’s band.

The lullaby-like collabo has been in the works since early 2014, when the two met in a bungalow in Los Angeles, according to a statement from West’s label Def Jam recording.

Some comments posted on Twitter suggested this generation have no idea who Paul McCartney is.

I don’t know who Paul McCartney is, but Kanye is going to give this man a career w/ this new song!!

“The process that would result in ‘Only One’ began with a simple brainstorming session between the two, with McCartney improvising on the keyboards and Kanye vocally sketching and shaping ideas in a stream-of-consciousness riff,” Def Jam said.

The song was inspired by West’s daughter North, who was sitting in his lap when he sang to her “Hello my only one.”

West said his own mother used to sing those words to him as a child.

“My mom was singing to me, and through me to my daughter,” said West, whose first name also means “only one.”

Def jam called the collaboration “one of the most powerful and unexpected music collaborations in modern history.”

The single was released late New Years Eve, and will be available on iTunes in 119 countries for one week.